From across the galaxy, wild reports reach Starfleet’s ears. Sensor readings pick up gravimetric distortions that cause chaos in planetary atmospheres, disturb stellar phenomena or agitate nebula particles. Ships are going missing, or appearing as if from nowhere, thousands of light-years from their last known location.

Those that can communicate speak of being dragged into what they thought was a wormhole, a subspace passageway of branching tunnels and chaotic turbulence their ship tumbled through before falling out of another exit point. It defies all known records of any wormhole – but readings and descriptions do match another phenomena, barely known to Starfleet and ill-understood: Underspace.

This network of subspace corridors was first encountered by Starfleet through the journey of the USS Voyager. Complex, dangerous, and labyrinthine, these passageways once enabled the long-dead Vaadwaur to build one of the largest empires the galaxy has ever known before their eventual downfall. Now, only their former vassals, the Turei, understand enough of Underspace for it to be safely traversed. Since then, Starfleet has only accessed Underspace with the help of the Turei, and has never known its tunnels to reach any further than the Delta Quadrant. Until now.